Genetic Analysis Of Rice Grain Shape And Fine Mapping Of QGW2

Food is the foundation of human existence and development, which is the prerequisite of human civilization’s survival and development. With the deterioration of the global climate and bad environmental resources and reduction in arable land, grain acreage and productivity decreased. Therefore, how to increase food production has become an issue of universal concern. Rice (Oryza sativa L) is one of the most important crops. Grain yield in rice is a complex trait multiplicatively determined by its three component traits:number of panicles, number of grains per panicle, and grain weight. Grain weight as one of yield components factors directly affect the yield of rice, while the main factors affecting grain weight including grain width, grain length, grain thickness and aspect ratio. In this paper, we used93-11and Peiai64s for the parents to build132recombinant inbred lines as experimental materials, for research and analysis QTLs of grain length, grain width and grain weight. With high-density genetic linkage map of rice initially mapping QTLs of the grain length, grain width and grain weight. Then utilization of BC2F2and low generation recombinant inbred lines, application map-based cloning approach to fine mapping the main rice grain width effect QTL qGW2. The results were summarized as follows:First, a total of11QTLs were detected in Hangzhou, including3QTLs for grain length,8QTLs for grain width, but had no QTLs were detected for grain weight; A total of10QTLs were detected in Hainan, including3QTLs for grain length,3QTLs for grain width, and3QTLs for grain weight.Second, among QTLs that controlling grain length, qGL1.1and qGL3were both detected in Hainan and Hangzhou respectively, while qGL1.2was only detected in Hangzhou and qGL8was only detected in Hainan.Third, among QTLs that controlling grain width, qGW2was both detected in Hainan and Hangzhou respectively, while7QTLs such as qGW1, qGW4, qGW5.1,qGW6, qGW7.1, qGW7.2and qGW9were only detected in Hangzhou, qGW5and qGWll were only detected in Hainan.Fourth, among QTLs that controlling grain weight, no QTL was detected for grain weight in Hangzhou, while4QTLs such as qTGW2, qTGW5, qTGW6and qTGW7were detected in Hainan.Fifth, this5QTLs such as qGWl, qGW4, qGW9, qGL1.2and qTGW6additive effect from Peiai64s, while the other QTLs additive effect from93-11. The QTL qGL1.1and qGW2control of grain length and grain width have the maximum contribution rate, respectively, reach to16.2%and13.5%.Sixth, large-scale use93-11and PA64s RIL population and PA64s backcross and selfing produced BC2F2population, fine mapping qGW2in90kb physical distance between markers TT27and TT28.